JP2004106978A - Recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce fluctuation in a head and an intersheet distance, to reduce a cockling height, and to prevent an ink droplet from being shifted in point of impact. <P>SOLUTION: A plurality of protrusions 9 and a plurality of recesses 10 extended along a sheet conveying direction are arranged alternately in a platen 7. A flapping holding spur 11 is supported rotatably by a torsion coil spring 12 in a downstream side of a recording area, and brought into pressure contact onto the recesses 10. A pair of ejection rollers 13 is provided in a substantial downstream side of the protrusions 9. Although a recording sheet S is bulged projectingly to a recording head 1 side by cockling caused by swelling, the sheet S does not contact with the recording head 1 since a considerable amount thereof is absorbed in the recesses 10, and a P-P (abbreviation of "peak to peak") is also suppressed to a lower level. After a tip of the recording sheet S is passed through the the ejection rollers 13, a ridge of the cockling is crashed by a conveying spur 13b, and is broken up between the flapping holding spur 11 and the conveying spur 13b to lower the P-P more. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for performing recording on a sheet by a recording unit, and more particularly, to a recording area of an ink jet recording apparatus that performs recording by discharging ink droplets from an ink jet recording unit and a configuration of the apparatus before and after the recording area.
[0002]
[Prior art]
In order to perform stable printing with an ink jet printing apparatus, wrinkles generated when ink is applied to a printing sheet, which is a printing medium, and the influence of a wavy shape (hereinafter referred to as cockling) are eliminated as much as possible. Therefore, it is necessary to prevent the recording sheet that has been curled due to the influence from floating on the recording head side so as to maintain the space between the recording sheet surface and the recording head. This is because if the height of the recording sheet rises to such a degree that the recording sheet comes into contact with the recording head, ink droplets adhering to the recording head are transferred, and unfixed ink applied to the recording sheet itself is rubbed. This causes the recording sheet to be soiled, and at the same time, causes a problem such as clogging of the ink discharge port itself of the recording head.
[0003]
Conventionally, a technique for solving the above-described problem has been disclosed (for example, see Patent Documents 1 and 2).
[0004]
[Patent Document 1]
JP 2000-071532 A
[Patent Document 2]
JP 2000-158644 A
First, a first conventional example related to Patent Document 1 will be described with reference to FIGS.
[0005]
The ink jet recording apparatus 100 includes a conveying roller 102 serving as a sheet conveying unit and a pinch roller 103 which is pressed and rotated by the conveying roller 102 at a position upstream of the recording head 101 in the recording sheet conveying direction. And a paper ejection spur 105 which is pressed against and rotated by the rotation. Further, a platen 106 for guiding the back surface of the recording sheet S is provided at a position opposed to the recording head 101, and a plurality of ribs 107 for forming a wave in the sheet material width direction of the recording sheet S are provided on the upper surface of the platen 106. The concave portions 108 are formed alternately. A sheet material holding plate 110 having a projection 109 for guiding the recording sheet S into each concave portion 108 is provided upstream of the platen 106 in the recording sheet conveyance direction. Further, a waving holding spur 112 for pressing the recording sheet S in the direction of each of the concave portions 108 is similarly provided downstream of the concave portion 108 in the recording sheet conveying direction. The above-described discharge roller 104 and discharge spur 105 are located downstream of each rib 107 of the platen 106 in the sheet conveyance direction. The height of the nip formed by the discharge roller 104 and discharge spur 105 is And are arranged at substantially the same height.
[0006]
With the above configuration, the behavior of the recording sheet S on the platen 106 will be described with reference to FIG.
[0007]
The recording sheet S that has passed through the sheet material holding plate 110 is given a wavy shape as shown by a solid line S5 in FIG. At this time, when the recorded image has a high density, a large amount of recording ink using water as a main solvent is injected, and the recording sheet S swells. Here, since the top of the wavy shape of the recording sheet S is pressed by the rib 107 and the horizontal portion 111 of the sheet material pressing plate 110 immediately before the recording area, the recording sheet S does not easily move due to swelling. Conversely, since movement is not restricted in the plurality of recesses 108, the swelling of the recording sheet S mainly occurs in the recesses 108. Since the projection 109 has been displaced downward in advance, cockling surely occurs downward, and the recording sheet S after recording is as shown by a broken line S6 in FIG. Then, when the recording sheet S on which the cockling is formed as shown in S6 in the recording area is further conveyed, the paper ejection roller 104 and the paper ejection spur 105 maintain the cockling state by the waving holding spur 112. However, since these paper discharge roller pairs are arranged downstream of the plurality of ribs 107, they are positioned at the peaks of the cock ring, and also maintain the cock ring state.
[0008]
Further, although the recording sheet S is curled due to the atmospheric environment, the recording sheet S is given a wavy shape upstream of the recording area, and the wavy holding spur is maintained even after the rear end of the recording sheet S has passed through the sheet material holding plate 110. 112 keeps the wavy shape. Therefore, the stiffness of the recording sheet S is increased, and the curl is also corrected, so that the recording sheet S is prevented from floating on the recording head 101 side.
[0009]
Next, a second conventional example related to Patent Document 2 will be described with reference to FIGS. Here, the same description as the first conventional example will not be repeated.
[0010]
The inkjet recording apparatus 200 includes a transport roller 202 serving as a sheet transport unit and a pinch roller 203 that is pressed against and driven by the transport roller 202 upstream of the recording head 201 in the recording sheet transport direction, and has a discharge roller 204 downstream thereof in the sheet transport direction. , And has a paper ejection spur 205 that is pressed into contact therewith and driven to rotate. Further, a platen 206 for guiding the back surface of the recording sheet S is provided at a position facing the recording head 201, and a plurality of ribs 207 for forming a wavy shape in the sheet material width direction of the recording sheet S are provided on the upper surface of the platen 206. , A plurality of auxiliary ribs 208 having a lower height than the ribs 207 are provided. The transport roller 202 and the pinch roller 203 located upstream of the platen 206 in the recording sheet transport direction have the pinch roller 203 with respect to the transport roller 202 as shown in FIG. It is arranged so that it is offset in the direction, and its nip position is located above the rib 207. Therefore, the recording sheet S is conveyed so as to be pressed obliquely from above against the rib 207, and as shown by a solid line S7 in FIG. Thus, a wavy shape that forms a valley is provided. Further, the above-described paper discharge roller 204 and paper discharge spur 205 are located downstream of each rib 207 of the platen 206 in the sheet transport direction, and similarly downstream of the recording sheet S between the ribs 207, the recording sheet S is moved between the ribs 207. , And a waving spur 209 for pressing between the paper discharge rollers 204.
[0011]
In the configuration described above, the behavior of the recording sheet S on the platen 206 has a wavy shape as shown by a solid line S7 before recording by the recording head 201 as shown in FIG. Is recorded, the swelling of the recording sheet S extends between the rib 207 and the auxiliary rib 208 in a direction away from the recording head 201, as shown by S8 indicated by a broken line.
[0012]
[Problems to be solved by the invention]
However, in the configuration shown in the above conventional example, the first problem is that the depth of the wavy valley imparted to the recording sheet changes before and after the leading end portion of the recording sheet reaches the waving holding spur. Can be This is because the wavy shape (depth of valley and valley) formed by the offset of the sheet material holding plate 110 and the pinch roller 203 with respect to the transport roller 202 upstream of the recording head naturally depends on the thickness and rigidity of the recording sheet. Further, even in one sheet, it differs depending on the location due to the density of the fiber and the like. However, the height of the waving holding spurs (112, 209) is set at a position lower than the ribs 107 and 207 in consideration of the component tolerance and the mounting tolerance in order to securely push the recording sheet between the ribs 107 and 207. ing. Therefore, in many cases, the depth of the valley increases after the leading end of the recording sheet reaches the waving holding spur. Here, the waving holding spur 209 is rotatably supported by a torsion coil spring 210 so as to be elastically movable, and is configured to be movable to some extent in the height direction due to the rigidity of the recording sheet. Since it is provided to give a shape, the influence cannot be completely eliminated.
[0013]
As a result, the distance from the recording head to the recording surface of the recording sheet changes before and after the leading end of the recording sheet reaches the waving spur, and in forming an image, scanning of the recording head is performed in the same manner as a plurality of paper feeds. In repeated multi-pass printing or the like, a shift occurs in the landing position of the ink droplet, which may cause a color shift of the image or a feeling of stickiness.
[0014]
Further, as a second problem, when a high-density recording image is recorded on a recording sheet, as described in the description of the conventional example, the swelling of the recording sheet is caused by a wavy valley portion previously applied to the recording sheet. That is, it is generated between the concave portion 108 of the platen, the rib 207, and the auxiliary rib 208 in a direction away from the recording head, thereby preventing contact with the recording head. However, there is also an adverse effect, and in a portion where cockling occurs, the recording surface of the recording sheet moves away from the recording head, and the landing deviation of ink droplets increases. Also, in the unrecorded area to be recorded in the future, the valley portion has moved away from the recording head due to the influence of the large waving in the area where cockling has occurred, and the landing deviation of ink droplets has increased similarly.
[0015]
A third problem is that the depth of the wavy valley imparted to the recording sheet changes before and after the rear end of the recording sheet passes through the conveying rollers (102, 202). This is caused by a state where the non-recording surface of the recording sheet is supported by the transport rollers over the entire area in the width direction, and the state is such that only the ribs 107 and 207 of the platen are supported. In other words, before the trailing edge of the recording sheet passes through the conveyance roller, the conveyance roller portion supports the entire width of the recording sheet when trying to provide a wavy shape that forms a trough between the ribs 107 and 207 of the platen. Because it is affecting its drag. However, after the trailing edge of the recording sheet has passed through the conveying roller, the drag is lost, and the depth of the valley increases. As a result, the landing positions of the ink droplets may be misaligned, and the image may have a color misalignment or a sense of stickiness.
[0016]
The present invention has been made in view of the above problems, and an object of the present invention is to prevent a recording head and a recording sheet from coming into contact with each other due to the effects of cockling and curling, and to prevent the recording sheet from a leading end to a trailing end. It is an object of the present invention to provide a recording apparatus that maintains a distance between a recording head and a recording surface of a recording sheet (hereinafter, referred to as a head-to-sheet distance) without changing over the entire area. Another object of the present invention is not to generate cockling that occurs when a high-density recording image is recorded, but to generate the cockling in a direction away from the recording head, but to grow it toward the recording head and to reduce the cockling. By reducing the height difference between peaks and valleys (hereinafter, referred to as peak-to-peak), it is possible to prevent contact with the recording head and to minimize the deterioration of landing deviation of ink droplets. It is in.
[0017]
[Means for Solving the Problems]
In order to achieve the above object, a recording apparatus according to a first aspect of the present invention is arranged such that a conveying unit that conveys a recording sheet and a position facing a recording head that performs recording on the recording sheet, In a recording apparatus comprising a platen on which a plurality of concave portions and convex portions extending are formed,
A rotatable rotator is provided at a position downstream of the recording head in the conveyance direction and facing the recesses in a pressure-contact manner.
[0018]
Further, a rotatable rotator may be provided downstream of the recording head in the transport direction and in pressure contact with a position facing each projection.
[0019]
Further, it is preferable that the step between each convex portion and each concave portion at the position where the rotating body is arranged is at least 0.5 mm or less, and this value is such that the wavy shape given upstream in the transport direction is It is good to decide according to how many PPs are kept.
[0020]
According to the first aspect, since the rotating body corresponding to the waving spur in the above-described conventional example is rotatably pressed into the recess of the platen, the height of the rotating body is reliably determined, In addition, since the depth of the wavy valley of the recording sheet is also determined by the concave portion, the head-to-sheet distance can be stably maintained over the entire area from the leading edge to the trailing edge of the recording sheet.
[0021]
Also, when a high-density recording image is recorded, a peak is formed in the convex portion of the platen and a valley is formed in the concave portion, so that the platen grows in a direction in which the amplitude of the undulation increases. Since the height of the valley in the wavy shape is determined by the concave portion of the platen and is held down by the rotating body, the swelling of the recording sheet is absorbed so that the bottom of the valley is widened, and cannot be absorbed here. The swelling of the recording sheet spreads over the wavy crests and grows as cockling so as to slightly rise toward the recording head. Here, when the leading end of the recording sheet reaches the pair of conveying rollers arranged downstream in the conveying direction, the peak of the cock ring is crushed, and the peak of the cock ring is formed between the rotating body (wavy spur) and the pair of conveying rollers. Split. That is, since one peak is divided into two to lower the PP, it is possible to prevent landing of ink droplets as much as possible while preventing contact with the recording head.
[0022]
The recording apparatus according to the second aspect of the present invention is arranged at a position facing a conveying unit for conveying the recording sheet and a recording head for recording on the recording sheet, extending in the conveying direction of the recording sheet, and having a height. A platen having at least two or more types of projection groups having different heights, including a plurality of first projections composed of the highest projections and a plurality of second projections composed of projections having a height lower than each of the first projections. A recording device comprising:
A rotatable rotator is provided downstream of the recording head in the direction of conveyance in contact with at least one of the second protrusions.
[0023]
Here, a rotatable rotator may be provided at a position downstream of the recording head in the conveying direction and opposed to each of the first protrusions in pressure contact.
[0024]
Further, it is preferable that the step between each of the first protrusions and the protrusion of the second protrusion to which the rotating body is pressed is at least 0.5 mm or less. The shape is preferably determined according to the number of PPs in the recording area.
[0025]
Further, a plurality of first projections, which are formed on a platen arranged at a position facing the recording head and extend in the recording sheet conveyance direction, and include a plurality of recesses, a plurality of projections, and a projection having the highest height. And a plurality of second protrusions each having a height lower than each of the first protrusions, a portion of the second protrusion pressed against the rotating body is formed by a roller member rotatably supported by a platen, The upper part of the outer periphery of the member may have substantially the same height as the upstream in the transport direction.
[0026]
According to the second aspect, the rotating body corresponding to the waving spur in the above-described conventional example is rotatably pressed against at least one of the plurality of second projections of the platen, and thus is reliably disposed. Since the height of the rotator is determined, and the depth of the wavy valley of the recording sheet is also determined by the second protrusion, the head-sheet distance is reduced over the entire area from the leading edge to the trailing edge of the recording sheet. It is possible to keep it stable.
[0027]
When a high-density recording image is recorded, at least one of the highest protrusion and the second protrusion of the plurality of protrusions of the platen is press-contacted rotatably in advance. Since the wavy shape that becomes a valley is provided in the portion having the rotating body, the undulation grows in a direction in which the amplitude of the waving increases. Although the height of the valley portion in the wavy shape is determined by the second protrusion of the platen, the valley portion grows as a cockling in a direction in which the valley becomes slightly deeper between the protrusions, and cannot be absorbed here. The swelling of the recording sheet spreads to the peak portion of the wavy shape, that is, the highest projection portion, and grows as cockling so as to slightly rise to the recording head side. Next, when the leading end of the recording sheet reaches the pair of conveying rollers disposed downstream in the conveying direction, the peak of the cock ring is crushed, and the peak of the cock ring is formed between the rotating body (wavy spur) and the pair of conveying rollers. Split. That is, since one peak is divided into two to lower the PP, it is possible to prevent contact with the recording head and to minimize deterioration of landing deviation of ink droplets.
[0028]
The recording apparatus according to a third aspect of the present invention includes a conveying unit that conveys the recording sheet, a plurality of recesses that are disposed at a position facing a recording head that performs recording on the recording sheet, and extend in a conveying direction of the recording sheet. And a platen having a convex portion,
A rotatable rotator that is disposed downstream of the recording head in the transport direction and that faces each of the recesses and that is supported so as to be elastically movable at least in a height direction, and the rotator that faces the rotator A slit is formed in the recess so that the rotating body does not come into contact with the rotating body. In a state where the recording sheet is absent, the lower part of the outer circumference of the rotating body has substantially the same height as each of the recesses, and one of the slits. Is held so as to be located at the position indicated by.
[0029]
In addition, the apparatus further includes another rotatable rotator that is disposed downstream of the recording head in the transport direction and that faces the plurality of convex portions of the platen, and is supported so as to be elastically movable at least in the height direction. A separate slit is formed in each convex portion facing the rotating body so that another rotating body does not contact, and in the state where there is no recording sheet, the outer peripheral lower part of another rotating body is substantially the same as each convex portion. It may be held at the same height and located in any of the other slits.
[0030]
Further, the step between each projection at the position where another rotating body is disposed and each recess at which the slit is formed may be at least 0.5 mm or less, or may be located downstream in the transport direction of the recording head. The transporting means may have a transport roller pair for nipping and transporting the recording sheet substantially downstream of each convex portion in the transport direction.
[0031]
The recording apparatus according to a fourth aspect of the present invention is arranged such that a conveying unit that conveys the recording sheet, and a position facing a recording head that performs recording on the recording sheet, extend in a conveying direction of the recording sheet, and have a height. At least two or more types of projection groups having different heights, including a plurality of first projections composed of the highest projections and a plurality of second projections composed of projections having a height lower than each of the first projections. A printing apparatus provided with a platen, which is disposed at a position facing at least one type of each of the second protrusions downstream of the recording head in the transport direction, and is rotatably supported so as to be elastically movable at least in a height direction. And a slit formed in the projections of the projection group facing the rotating body so that the rotating body does not come into contact with the projection. Part is, the rotating body is characterized in that it is held so as to be positioned in any of the projection group of projections having substantially the same height, and said slit facing.
[0032]
A rotatable rotating body disposed downstream of the recording head in the transport direction and facing the first protrusion, and rotatably supported at least in a height direction so as to be elastically movable; There is another slit formed on the projection of the projection group facing the other rotation body so that another rotation body does not come into contact.In the state where there is no recording sheet, the lower periphery of another rotation body faces another rotation body. It may be held so as to be located at substantially the same height as the projections of the projection group to be formed and in any of the other slits.
[0033]
Further, it is preferable that the step between each of the first protrusions on which another rotating body is disposed and each of the second protrusions provided with the slit is at least 0.5 mm or less.
[0034]
Further, a roller member having a groove-shaped slit portion facing each of the rotating body and another rotating body is rotatably supported by the platen, and both side portions of the groove shape of the roller member are transported by the platen. It may be located at substantially the same height as the surface upstream in the direction.
[0035]
Further, the transporting means located downstream of the recording head in the transport direction may have a pair of transport rollers for nipping and transporting the recording sheet substantially downstream of the first protrusion in the transport direction.
[0036]
Further, the platen has a plurality of concave portions and convex portions extending in the recording sheet transport direction, and a wavy shape in which the convex portion forms a peak with respect to the recording sheet and the concave portion forms a valley upstream of the recording head in the transport direction. May be provided.
[0037]
Further, the waving shape imparting means has a pair of conveying rollers positioned upstream in the conveying direction of the recording head, a convex portion and a concave portion, and the nip position of the pair of conveying rollers is located above the convex portion, and the conveying roller The roller that contacts the non-recording surface of the recording sheet of the pair is offset from the recording head toward the recording head, so that the recording sheet is pressed against the platen. Alternatively, the waving shape imparting means may be a sheet guide member for guiding the recording sheet to the convex portion and the concave portion, and may have a projection for guiding the recording sheet to the concave portion. In this case, the projection of the sheet guide member may be elastically deformable.
[0038]
According to the third and fourth aspects, the same effects as those of the first and second aspects can be obtained, and the rotating body does not come into contact with the platen when there is no recording sheet. For example, even when a spur having a plurality of protrusions on the outer peripheral surface is used as the rotating body, the spur is not damaged. Further, the slit formed here is of such a width as to avoid contact with the rotating body, but not so wide that the recording sheet is pushed between the slits.
[0039]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
A recording apparatus according to a first embodiment of the present invention will be described with reference to the drawings.
[0040]
FIG. 1 is a perspective view of the recording apparatus according to the present invention in which a part around a platen is cut away, and FIG. 2 is a sectional view taken along line AA in FIG.
[0041]
In FIG. 1, a recording head 1 is mounted on a carriage 2, and the carriage 2 is driven by a carriage motor (not shown) via a timing belt 3. The carriage 2 is supported by a guide rail 4 and a support rail 6 provided on a chassis 5. It is supported and scans back and forth on the platen 7.
[0042]
On the other hand, the recording sheet S is transported by a feeding mechanism (not shown) to a nip position of the transport roller pair 8 including the transport roller 8a and the pinch roller 8b, and skew is corrected. Here, the pinch roller 8b receives the urging force of the pinch roller spring 8d via the pinch roller holder 8c, and is urged by the transport roller 8a. Thus, the pinch roller 8b is driven by the rotation of the transport roller 8a, and can pinch and transport the recording sheet S. At this time, the pinch roller 8b is urged at a position offset to the downstream side in the transport direction with respect to the transport roller 8a as shown in FIG. 2, and the nip position of the transport roller pair 8 is located above the platen 7. The recording sheet S is conveyed so as to be pressed against the platen 7 from obliquely above.
[0043]
The platen 7 has a plurality of convex portions 9 and concave portions 10 extending in the sheet conveying direction alternately arranged at intervals of 20 to 40 mm on the conveying surface thereof. Therefore, when the recording sheet S is pressed against the platen 7 by the conveying roller pair 8, the recording sheet S is given a wavy shape in which the convex portion 9 becomes a peak and the concave portion 10 becomes a valley. Here, the step between the convex portion 9 and the concave portion 10 is preferably 0.5 mm or less, and this value is the position of the above-described wavy valley in the recording area of each recording device, specifically, the recording range of the recording head 1. It is better to set the height below.
[0044]
Further, a waving spur 11 is disposed in the concave portion 10 downstream of the recording area, and the center of rotation thereof is rotatably supported by the torsion coil spring 12 and is pressed against the concave portion 10. As a result, when the leading end of the recording sheet S reaches the waving spur 11, the waving spur 11 moves upward by the thickness of the recording sheet S while rotating, and the recording sheet S is moved to the waving spur 11 We can lead in between. Here, the "spur" is a disk-shaped object having a plurality of sharp projections provided on the outer periphery thereof, the sharp projections abutting on the recording surface of the recording sheet with a small area, and the recording sheet S is located downstream of the recording area. When there is unfixed ink on the upper side, it assists recording sheet conveyance without disturbing the recorded image. Here, in the case where the recording apparatus uses ink having good fixing properties, the recording apparatus is not limited to spurs, and may be, for example, a molded simple disk shape.
[0045]
A discharge roller pair 13 including a discharge roller 13a and a conveying spur 13b is provided substantially downstream of the convex portion 9. Here, the discharge roller 13a is formed by press-fitting a discharge roller 13a formed of an elastic material such as rubber on a discharge roller shaft 13c. The transport spur 13b is rotatably supported at its rotation center by the torsion coil spring 12, and is urged by the paper discharge roller 13a. Accordingly, the transport spur 13b is driven by the rotation of the paper discharge roller 13a, and can pinch and transport the recording sheet S.
[0046]
In such a configuration, the recording sheet S on which recording has been completed is conveyed and stored in a discharge tray (not shown).
[0047]
Next, the behavior before the recording of the recording sheet S and when a high-density recording image is recorded will be described with reference to FIGS. 3A and 3B show the state before the leading end of the recording sheet S reaches the waving spur 11, and FIG. 3B shows the state of the recording sheet S. FIG. 3C shows a state in which the leading end of the recording sheet S has passed the discharge roller pair 13, and FIG. 3D shows a state in which the trailing end of the recording sheet S has the conveying roller. This represents the state after passing through pair 8. A solid line S1 representing the recording sheet S in each drawing indicates a recording sheet in an unrecorded state before recording by the recording head 1 or a low-density recording image, and the recording sheet almost swells. A broken line S2 indicates a state where a high-density recording image is recorded, the recording sheet S swells, and cockling occurs.
[0048]
First, in FIG. 3A to FIG. 3D, a recording sheet in an unrecorded state before recording, or a low-density recorded image, which is indicated by a solid line S1, is recorded, and almost no swelling occurs. The recording sheet will be described.
[0049]
First, the behavior before the leading end of the recording sheet reaches the waving spur 11 will be described. The recording sheet S <b> 1 is conveyed while being pressed against the platen 7 by the conveying roller pair 8, so that the recording sheet S <b> 1 is provided with a wavy shape in which the projections 9 have peaks and the recesses 10 have valleys. Here, since the step between the convex portion 9 and the concave portion 10 is set to be equal to or less than the height of the above-described wavy valley in the recording range, the non-recording surface of the recording sheet S1 located in the valley contacts the concave portion 10. are doing. Since the peaks are pressed against the projections 9 by the pair of conveying rollers 8, the non-recording surface is also in contact with the projections 9. (State of FIG. 3A)
Next, the state in which the leading end of the recording sheet has passed the waving spur 11 will be described. Originally, the wavy holding spur 11 was arranged in a state of being pressed against the concave portion 10, so that the waving holding spur 11 was only raised by the thickness thereof with the conveyance of the recording sheet S1, and the posture and the head of the recording sheet S1 were changed. -There is no change in the distance between the sheets. (State of FIG. 3B)
Next, a state in which the leading end of the recording sheet has passed through the discharge roller pair 13 will be described. (The paper discharge roller 13a is not shown in FIG. 3.) Also here, the paper discharge roller pair 13 is provided substantially downstream of the convex part 9, and the height of the nip thereof is substantially the same as that of the convex part 9. 3A, the conveying spur 13b simply rises by the thickness thereof with the conveyance of the recording sheet S1, and there is no change in the posture of the recording sheet S1 or the distance between the head and the sheet (FIG. 3C). Status).
[0050]
Finally, a state in which the rear end of the recording sheet has passed the pair of conveying rollers 8 will be described. Here, the pressing force of the conveying roller pair 13 against the platen 7 is lost, but the peak portion of the recording sheet S1 is held by the sheet discharging roller pair 13, and the valley portion is pressed against the concave portion 10 by the waving holding spur 11. Therefore, the posture of the recording sheet S1 and the distance between the head and the sheet do not change. Further, in the present embodiment, since the waving holding spur 11 is disposed upstream of the discharge roller pair 13 in the recording sheet conveyance direction, the weight of the leading end portion of the recording sheet that has already passed through the discharge roller pair 13 causes Even if the recording sheet bows with the discharge roller pair 13 as a base point, that is, even if the leading end of the recording sheet hangs down, the trailing end of the recording sheet does not rise to the recording head 1 side. (State of FIG. 3D)
As described above, according to the present invention, when a recording sheet in an unrecorded state before recording by the recording head 1 or a low-density recording image is recorded, and the recording sheet hardly swells, Since the shape and the distance between the head and the sheet do not change from the leading edge to the trailing edge of the recording sheet, it is possible to prevent the ink droplets from landing misalignment.
[0051]
Further, although the recording sheet is curled due to the atmospheric environment, a wavy shape is provided upstream of the recording area, and the wavy shape is maintained by the wavy spur 11 even after the rear end of the recording sheet has passed through the pair of conveying rollers 13. Therefore, the stiffness of the recording sheet S is increased and the curl is also corrected, so that the recording sheet S is prevented from floating on the recording head 1 side.
[0052]
Next, a description will be given of a state in which a high-density recording image is recorded on a recording sheet and cockling occurs, which is indicated by a broken line S2 in FIGS.
[0053]
First, the behavior before the leading end of the recording sheet reaches the waving spur 11 will be described. When a high-density recording image is recorded, the swelling of the recording sheet S2 is basically determined by the undulation, since a ridge is formed in the convex portion of the platen 7 and a valley is formed in the concave portion. Attempts to absorb by increasing. However, since the height of the valley portion is determined by the concave portion 10 of the platen 7, the swelling of the recording sheet S2 is absorbed so that the bottom surface of the valley portion is widened. The ripple spreads over the undulating ridge, and grows as cockling so as to slightly rise toward the recording head 1 (the state of FIG. 3A).
[0054]
Here, in the conventional example, since the valley portion is not supported, the swelling of the recording sheet S2 is absorbed by the valley portion falling down. As a result, the peak portion hardly swells toward the recording head 1, but the PP increases accordingly, and as a result, the head-sheet distance in the area to be recorded from now on also increases. On the other hand, in the present embodiment, the bottom surface of the valley portion expands, but the distance between the head and the sheet does not increase, and the ridge portion slightly rises toward the recording head 1, but the swelling of the recording sheet S2 occurs at the valley portion. Since a considerable amount has been absorbed, it is not so much as to come into contact with the recording head 1.
[0055]
Next, the state in which the leading end of the recording sheet has passed the waving spur 11 will be described. Originally, the wavy holding spur 11 was disposed in a state of being pressed against the concave portion 10, so here, the waving holding spur 11 only rose by the thickness thereof with the conveyance of the recording sheet S2, and the state of the recording sheet S2 was changed. Is the same as the state shown in FIG. 3A (the state of FIG. 3B).
[0056]
Next, a state in which the leading end of the recording sheet has reached the paper discharge roller pair 13 will be described. Here, the nip height of the paper discharge roller pair 13 is arranged at substantially the same height as the convex portion 9, so that the cock ring peaks while floating from the convex portion 9 as shown in FIG. Is reached, this mountain is crushed and divided into the left and right sides of the transport spur 13b, that is, between the waving spur 11 and the transport spur 13b. Therefore, when one mountain is divided into two, the PP is further reduced as compared with the conventional example (the state of FIG. 3C).
[0057]
Finally, a state in which the rear end of the recording sheet has passed the pair of conveying rollers 8 will be described. Here, as described above, the trailing edge of the recording sheet does not rise due to bowing of the leading end of the recording sheet, and the state of the recording sheet S2 is the same as the state shown in FIG. 3C (the state of FIG. 3D). .
[0058]
As described above, in the present invention, a high-density recording image is recorded, and even when cockling occurs, the valley of the cockling does not fall below a predetermined height, and the bottom surface of the valley expands As a result, the swelling is absorbed, and the swelling that cannot be absorbed here spreads to the wavy crests, and grows as cockling so as to slightly rise toward the recording head 1 side. Since a considerable amount has been absorbed, it is possible not to make contact with the recording head 1 but also to keep PP low. Further, after the leading end of the recording sheet has passed through the discharge roller pair 13, the number of peaks of the cock ring is doubled, so that the PP is further reduced. Therefore, it is possible to minimize the displacement of the landing of the ink, and it is also possible to prevent the contact with the recording head.
[0059]
Here, as a supplement, the swelling of the recording sheet can be suppressed lower as the number of peaks of the waving is larger. Therefore, in the form of imparting a wavy shape to a recording sheet in advance, it is pointed out that it is sufficient to increase the number of peaks from the beginning, but to impart a wavy shape to an originally flat recording sheet. The pitch of the peaks needs to be about 20 to 40 mm. If this is ignored and the number of peaks is to be increased, a portion that should become a valley becomes a peak, or an adjacent peak becomes one peak, and a phenomenon that the peak floats on the recording head side occurs. The reason why the number of cockling peaks can be doubled in the present invention is that, for a recording sheet having cockling and having a somewhat reduced rigidity, one peak is divided into two peaks by the transport spur 13b. is there.
[0060]
The recording device in each of the following embodiments is basically the same as the recording device of the first embodiment. Therefore, only the differences from the first embodiment will be described, and the same members will be denoted by the same reference numerals. I do.
(Second embodiment)
In the first embodiment, the only spurs arranged on the platen 7 are the wavy holding spurs 11 pressed against the concave portions 10. However, in the present embodiment, as shown in FIG. In addition, a convex spur 14 is also arranged on the convex 9. The convex spur 14 is arranged at substantially the same position as the waving spur 11 in the transport direction, and is configured such that the center of rotation thereof is rotatably supported by the torsion coil spring 15 and pressed against the convex 9. . By adopting such a configuration, in a recording sheet in an unrecorded state or a recording sheet in which swelling due to recording hardly occurs, the recording sheet can be more securely brought into close contact with the convex portion 9, and the cockling It is possible to double the number of peaks on the recording sheet in which the occurrence of occurs before the recording sheet reaches the discharge roller pair 13.
(Third embodiment)
In the present embodiment, as shown in FIG. 5, a notch 7a is formed in the platen 7, and a discharge roller pair 13 is disposed at the position of the notch 7a. As a result, the paper discharge roller pair 13 is arranged at substantially the same position as the waving spur 11 in the transport direction.
[0061]
However, in this case, in order to prevent the trailing edge of the recording sheet from floating after the trailing edge of the recording sheet has passed through the transport roller pair 8, the transport spur 13b is offset to the upstream side in the transport direction with respect to the discharge roller 13a, and It is necessary that the rear end be pressed against the platen 7. By adopting such a configuration of the present embodiment, the depth direction of the apparatus can be shortened and space saving can be realized.
(Fourth embodiment)
In the first embodiment, the recess 10 is configured to have the same height from the upstream to the downstream in the transport direction, but in the present embodiment, the recess on the upstream side is configured to be low as shown in FIG. . That is, the first recess 16 and the second recess 17 are provided on the platen 7. The step between the second concave portion 17 and the convex portion 9 is configured in the same manner as before, and the first concave portion 16 is configured to be lower than the second concave portion 17. In addition, at the position of the second concave portion 17 in the transport direction, it is located substantially directly below the recording position of the recording head 1. With such a configuration of the present embodiment, the amplitude of the wavy shape is configured to be larger in the range of the first recess 16 than in the range of the second recess 17. Is particularly effective when the distance from the pair of conveying rollers 8 to the recording position of the recording head 1 or when the length of the recording head 1 is long.
(Fifth embodiment)
In each of the embodiments described above, one type of the convex portion and one type of the concave portion are formed on the platen 7. However, as shown in FIG. There are different types of protrusions.
[0062]
In FIG. 7, a first protrusion 18, a second protrusion 19, and a third protrusion 20 having different heights are arranged on the platen 7. Of these projections, the first projection 18 is the highest, the second projection 19 is the lowest, and the third projection 20 is the lowest. Here, the step between the first convex portion 18 and the second convex portion 19 is preferably 0.5 mm or less, and this value is determined in the recording area of each recording device, specifically, in the recording range of the recording head 1. It is preferable to set the height to be equal to or less than the height at which the above-described wavy valley is located. The third protrusion 20 is disposed between the first protrusion 18 and the second protrusion 20. The waving spur 11 is configured to be pressed against the second projection 19.
[0063]
Next, the behavior before recording of the recording sheet S and when a high-density recording image is recorded will be described with reference to FIGS. 8A to 8D. 8A to 8C show the state before the leading end of the recording sheet S reaches the waving spur 11, and FIG. 8B shows the state of the recording sheet S. 8C shows a state in which the leading end of the recording sheet S has passed through the paper discharge roller pair 13, and FIG. 8D shows a state in which the trailing end of the recording sheet S has passed the transport roller. This represents the state after passing through pair 8. A solid line S3 representing the recording sheet S in each drawing represents a recording sheet in an unrecorded state before recording is performed or a state where a low-density recording image is recorded and swelling hardly occurs. Indicates a state in which a high-density recording image is recorded, the recording sheet swells, and cockling occurs.
[0064]
First, in FIG. 8A to FIG. 8D, a recording sheet in an unrecorded state before recording or a low-density recorded image, which is indicated by a solid line S3, is recorded and almost no swelling occurs. The recording sheet will be described. This is different from that of FIG. 3 used in the first embodiment in that the contact point of the wavy valley is changed from the concave portion 10 to the second convex portion 19, and the behavior of the recording sheet itself is changed. Since there is no change, detailed description is omitted.
[0065]
Next, a description will be given of a state in which a high-density recording image is recorded and cockling occurs, which is indicated by a broken line S4 in FIGS. 8A to 8D.
[0066]
First, the behavior before the leading end of the recording sheet reaches the waving spur 11 will be described. When a high-density recording image is recorded, a wavy shape in which a peak is formed in the first convex portion 18 and a valley is formed in the second convex portion 19 is given in advance. To be absorbed by increasing the amplitude of the waving. However, since the height of the valley portion is determined by the second convex portion 19, the valley portion is divided into two portions, and the valley portion is generated between the second convex portion 19 and the third convex portion 20 to cause swelling. Absorb. Although the swelling of the recording sheet that could not be absorbed here spreads to the wavy crests, the recording sheet is absorbed by the valleys more than in the first embodiment. The amount of protrusion toward the head 1 decreases (the state of FIG. 8A).
[0067]
Next, the behavior of the waving holding spur 11 when the leading end of the recording sheet 1 has passed the waving holding spur 11 is the same as that of the first embodiment, and the state of the recording sheet S4 is the same as the state shown in FIG. 8A. (State of FIG. 8B).
[0068]
Next, a state in which the leading end of the recording sheet has reached the paper discharge roller pair 13 will be described. Here, since the nip height of the paper discharge roller pair 13 is arranged at substantially the same height as the first convex portion 18, the nip height floats from the first convex portion 18 as shown in FIG. When the peak of the cockling arrives in this state, the peak is crushed and divided into the left and right sides of the carrier spur 13b, that is, between the waving spur 11 and the carrier spur 13b. Therefore, when one peak is divided into two, the PP is further reduced as compared with the conventional example (the state of FIG. 8C).
[0069]
Finally, a state in which the rear end of the recording sheet has passed the pair of conveying rollers 8 will be described. Here, as described above, the trailing edge of the recording sheet S2 is not lifted due to the bowing of the leading edge of the recording sheet, and the state of the recording sheet S2 is the same as the state shown in FIG. 3C (the state of FIG. 8D). .
[0070]
As described above, in the present embodiment, it is possible to further reduce the amount of swelling toward the recording head 1 in a state before reaching the waving spur 11 when cockling occurs. However, at that time, the distance between the head and the sheet in the valley slightly increases, and therefore, a film-type recording sheet in which cockling hardly occurs is suitable for the main apparatus. In this case, the distance between the head 1 and the first convex portion 18 is shortened as much as possible so that a high image can be obtained. Although it spreads, contact with the recording head 1 can be prevented.
[0071]
Here, in this embodiment, the spurs arranged on the platen 7 are only the waving holding spurs 11 abutting on the second projections 19, but as shown in the second embodiment, the first projections are spurs. The spurs 14 that abut against the spurs 18 may be arranged, and the discharge roller pair 13 may be arranged at substantially the same position as the spurs 11 in the transport direction as shown in the third embodiment. Further, as shown in the fourth embodiment, the upstream sides of the second and third convex portions 19 and 20 may be lowered by one step. In this embodiment, three types of convex portions are used. However, the present invention is not limited to this type, and it is preferable to provide at least two types.
(Sixth embodiment)
In each of the above-described embodiments, the waving spur 11 and the convex spur 14 are directly pressed into contact with the concave portion or the convex portion on the platen 7. However, the recording apparatus according to the present embodiment employs the platen 7 as shown in FIG. It has a configuration in which a rotatable roller is provided above.
[0072]
In FIG. 9, the convex roller 21 is rotatably provided on the platen 7 so that the outer peripheral upper surface thereof is substantially the same height as the convex 9 downstream of the recording area of the convex 9. Further, the concave roller 22 is rotatably provided on the platen 7 so that the outer peripheral upper surface is substantially the same height as the concave portion 10 downstream of the recording area of the concave portion 10. The convex roller 21 is pressed against the convex spur 14, and the concave roller 22 is pressed against the wavy holding spur 11.
[0073]
In the above-described configuration, the recording sheet S is sandwiched between the waving spur 11 and the rotatable concave roller 22 and between the convex spur 14 and the rotatable convex roller 21. The transport resistance of S can be reduced. In addition, since the convex roller 21 and the concave roller 22 are directly incorporated into the platen 7, it is easy to make the outer peripheral upper surfaces approximately the same height as the convex 9 and the concave 10, respectively. Therefore, the other effects are the same as the effects obtained in the second embodiment.
(Seventh embodiment)
In each of the above-described embodiments, the waving spur 11 and the convex spur 14 are directly pressed against the convex 9 and the concave 10 on the platen 7, but the recording apparatus of the present embodiment is shown in FIG. As described above, when the recording sheet S does not have the recording sheet S, the outer peripheral lower surface of the spur is kept equal to or less than the convex portion 9 or the concave portion 10 and a slit is provided on the platen 7 so that the spur does not contact the platen. ing.
[0074]
In FIG. 10, the waving spur 23 is supported by a torsion coil spring 25 so that its rotation center is rotatable and elastically movable in the height direction. The lower surface of the outer periphery is held by a spur holder (not shown) such that the height of the lower surface of the outer periphery is lower than or equal to the height of the recess 10. Similarly, the projection spur 24 is supported by a torsion coil spring 26 so that its rotation center is rotatable and elastically movable in the height direction. The lower surface of the outer periphery is held by a spur holder (not shown) so that the height of the lower surface of the outer periphery is lower than or equal to the height of the projection 9. Further, the concave portion 10 where the waving holding spur 23 is located is provided with a slit 27 to such an extent that the waving holding spur 23 does not contact. Similarly, a slit 28 is also provided in the convex portion 9 where the convex spur 24 is located. Accordingly, when the recording sheet S reaches the waving spurs 23 and 24, the waving spurs 23 and 24 rotate by the conveyance of the recording sheet S and move from the concave part 10 and the convex part 9 by the thickness of the recording sheet S. Move up. Here, the slits 27 and 28 have such a width that the spur holding spurs 23 and the convex spurs 24 do not come into contact with each other, so that the recording sheet S is not pushed between the slits 27 and 28 by these spurs. . Therefore, the posture of the recording sheet S is the same as that described in each of the above-described embodiments, in which the concave portion 10 has a wavy valley and the convex portion 9 has a peak.
[0075]
In the above configuration, before the recording sheet S reaches the waving spur 23 or the convex spur 24, the waving spurs 23 and 24 do not come into contact with the platen 7, so that the outer peripheral surface of the spur Damage to the provided projection is prevented. Conversely, these projections prevent the platen 7 from being scratched and the like, and it is possible to avoid jamming and damage caused by the recording sheet S being caught by the scratches. Other effects are the same as the effects obtained in the second embodiment.
(Eighth embodiment)
In the seventh embodiment, a slit is provided directly on the platen. However, in the recording apparatus of the present embodiment, as shown in FIG. 11, the slit portion is configured by rollers as described in the sixth embodiment. .
[0076]
The convex slit roller 29 has a small-diameter portion 29b in which the diameter of the portion corresponding to the convex spur 24 is smaller than the diameter of both side portions 29a, and the outer periphery of both side portions 29a downstream of the recording area of the convex portion 9. The upper surface is rotatably provided on the platen 7 so that the height is substantially the same as the height of the convex portion 9 on the upstream side in the transport direction of the recording sheet S. Similarly, the concave slit roller 30 has a small-diameter portion 30b in which the diameter of the portion corresponding to the waving holding spur 23 is smaller than the diameter of the both side portions 30a. The outer peripheral upper surface is rotatably provided on the platen 7 so that the concave portion 10 has substantially the same height as the upstream side in the transport direction of the recording sheet S. That is, the convex slit roller 29 and the concave slit roller 30 of the present embodiment are such that the small-diameter portions 29b, 30b between the side portions 29a, 30a function in the same manner as the slit described in the sixth embodiment. It is.
[0077]
As described above, in the configuration of the present embodiment, the effects of the sixth embodiment and the effects of the seventh embodiment can be obtained together.
[0078]
As described above, the embodiment has been described by using specific examples. However, it is needless to say that the recording apparatus may be configured by a combination of the embodiments described above. Further, as the waving means on the upstream side of the recording area, the description has been made with the same configuration as that of the second conventional example. However, the same structure as the first conventional example may be adopted, and the waving means on the upstream side is limited. It does not do.
[0079]
【The invention's effect】
As described above, according to the first aspect, the rotating body is rotatably pressed against the concave portion of the platen, so that the height of the rotating body is reliably determined and the valley of the wavy shape of the recording sheet is formed. Since the depth is also determined by the recess, the head-sheet distance can be stably maintained over the entire area from the leading edge to the trailing edge of the recording sheet.
[0080]
In addition, even when a high-density recording image is recorded, the wavy valley has a height determined by the concave portion of the platen, and is held down by the rotating body. Since the swelling of the recording sheet is absorbed and the peak of the cockling caused by the swelling of the recording sheet that has not been completely absorbed is divided into two by a pair of conveying rollers, the PP becomes lower. It is possible to eliminate landing deviation of ink droplets as much as possible.
[0081]
According to the second aspect, the rotating body is rotatably pressed against at least one of the plurality of second protrusions of the platen, so that the height of the rotating body is reliably determined and the recording is performed. Since the depth of the wavy valley of the sheet is also determined by the second protrusion, it is possible to stably maintain the head-sheet distance over the entire area from the leading edge to the trailing edge of the recording sheet.
[0082]
Further, according to the third and fourth inventions, the same effects as those of the first and second inventions can be obtained, and the rotating body does not come into contact with the platen when there is no recording sheet. Even when a spur having a plurality of protrusions on the outer peripheral surface is used as a body, the spur is not damaged.
[Brief description of the drawings]
FIG. 1 is a perspective view of a recording apparatus according to a first embodiment of the present invention.
FIG. 2 is a sectional view of the recording apparatus taken along line AA of FIG.
FIG. 3 is a view for explaining the behavior of a recording sheet in the view of the arrow B of the recording apparatus shown in FIG. 1;
FIG. 4 is a perspective view of a recording apparatus according to a second embodiment of the present invention.
FIG. 5 is a perspective view of a recording apparatus according to a third embodiment of the present invention.
FIG. 6 is a sectional view of a recording apparatus according to a fourth embodiment of the present invention.
FIG. 7 is a perspective view of a recording apparatus according to a fifth embodiment of the present invention.
8 is a view for explaining the behavior of the recording sheet as viewed from the direction of the arrow C of the recording apparatus shown in FIG. 7;
FIG. 9 is a perspective view of a recording apparatus according to a sixth embodiment of the present invention.
FIG. 10 is a perspective view of a recording apparatus according to a seventh embodiment of the present invention.
FIG. 11 is a perspective view of a recording apparatus according to an eighth embodiment of the present invention.
FIG. 12 is a perspective view of a recording apparatus according to a first conventional example.
13 is a view for explaining the behavior of the recording sheet in the direction of arrow D of the recording apparatus shown in FIG.
FIG. 14 is a perspective view of a recording apparatus according to a second conventional example.
FIG. 15 is a sectional view of the recording device taken along line EE of FIG. 14;
16 is a view for explaining the behavior of the recording sheet in the view of arrow F of the recording apparatus shown in FIG. 14;
[Explanation of symbols]
1 Recording head
2 carriage
3 Timing belt
4 Guide rail
5 Chassis
6 Support rail
7 Platen
8 transport roller pair
8a Transport roller
8b pinch roller
8c pinch roller holder
8d pinch roller spring
9 convex part
10 recess
11 Wave holding spur
12, 15 Torsion coil spring
13 Discharge roller pair
13a, 13b discharge roller
13c Discharge roller shaft
14 Convex spur
15 Torsion coil spring
16 First recess
17 Second recess
18 First convex part
19 Second convex part
20 Third convex part
21 Convex roller
22 concave roller
23 holding spur
24 convex spur
27, 28 slit
29 Convex slit roller
29a, 30a both sides
30 concave slit roller

Claims (20)

A recording apparatus comprising: a conveying unit that conveys a recording sheet; and a platen that is disposed at a position facing a recording head that performs recording on the recording sheet and has a plurality of concave portions and convex portions extending in a conveying direction of the recording sheet. In the device,
A recording apparatus, comprising: a rotatable rotating body that is disposed at a position downstream of the recording head in the transport direction and that faces the recesses in a pressure-contact manner. 2. The recording apparatus according to claim 1, further comprising a rotatable rotator disposed downstream of the recording head in the transport direction and at a position opposed to each of the protrusions. The recording apparatus according to claim 1, wherein a step between each of the convex portions and each of the concave portions at a position where the rotating body is arranged is at least 0.5 mm or less. Conveying means for conveying the recording sheet, a plurality of first protrusions disposed at a position facing a recording head for performing recording on the recording sheet, extending in the conveying direction of the recording sheet, and having the highest height; And a platen having at least two or more types of protrusion groups having different heights, including a plurality of second protrusions each having a height lower than each of the first protrusions.
A recording apparatus, comprising: a rotatable rotating body that is disposed in pressure contact with at least one of the second protrusions downstream of the recording head in the transport direction. 5. The recording apparatus according to claim 4, further comprising a rotatable rotator disposed at a position downstream of the recording head in a conveying direction and opposed to the first protrusions. The recording apparatus according to claim 4, wherein a step between each of the first protrusions and a protrusion of the second protrusions against which the rotating body is pressed is at least 0.5 mm or less. A plurality of first protrusions, each of which includes a plurality of recesses, a plurality of protrusions, and a protrusion having the highest height, provided on a platen disposed at a position facing the recording head in a direction in which the recording sheet is conveyed. And a portion of the plurality of second protrusions, each of which has a height lower than each of the first protrusions, that is pressed against the rotating body is formed of a roller member rotatably supported by the platen. The recording apparatus according to any one of claims 1 to 6, wherein an upper peripheral portion of the roller member has substantially the same height as an upstream portion in the transport direction. A recording apparatus comprising: a conveying unit that conveys a recording sheet; and a platen that is disposed at a position facing a recording head that performs recording on the recording sheet and has a plurality of concave portions and convex portions extending in a conveying direction of the recording sheet. ,
A rotatable rotator that is disposed downstream of the recording head in the transport direction and that faces each of the recesses and that is supported so as to be elastically movable at least in a height direction, and the rotator that faces the rotator A slit is formed in the recess so that the rotating body does not come into contact with the rotating body. In a state where the recording sheet is absent, the lower part of the outer circumference of the rotating body has substantially the same height as each of the recesses, and one of the slits. A recording apparatus characterized in that the recording apparatus is held so as to be positioned at a position indicated by a circle. A rotatable rotating body that is disposed downstream of the recording head in the transport direction and that faces the plurality of convex portions of the platen and that is supported so as to be elastically movable at least in a height direction; Each of the protrusions facing the rotating body is formed with another slit so that the another rotating body is not in contact with the other rotating body. The recording apparatus according to claim 8, wherein the recording apparatus is held so as to have substantially the same height as each of the protrusions and to be positioned in any of the other slits. The recording apparatus according to claim 8, wherein a step between each of the convex portions at the position where the another rotating body is disposed and each of the concave portions having the slit is at least 0.5 mm or less. 11. The conveying unit located downstream of the recording head in the conveying direction includes a pair of conveying rollers for nipping and conveying the recording sheet substantially downstream of the respective convex portions in the conveying direction. 12. Item 2. The recording device according to item 1. Conveying means for conveying the recording sheet, and a plurality of first protrusions, which are arranged at positions facing the recording head for performing recording on the recording sheet, extend in the conveying direction of the recording sheet, and have the highest height; A plurality of second protrusions each having a height lower than the first protrusions, and a platen having at least two or more types of protrusion groups having different heights.
A rotatable rotator that is disposed downstream of the recording head in the transport direction and that is opposed to at least one of the second protrusions and that is supported so as to be elastically movable at least in a height direction; A slit is formed in the projection of the projection group facing the body so that the rotating body does not contact, and in a state where the recording sheet is not present, a lower outer peripheral portion of the rotating body is opposed to the rotating body. A recording apparatus characterized in that the recording apparatus is held so as to be located at substantially the same height as the projections of the projection group and at any position within the slit. A rotatable rotating body disposed downstream of the recording head in the conveying direction and opposed to the first protrusion and supported at least in a height direction so as to be elastically movable; In the projections of the projection group opposed to each other, another slit is formed so that the another rotating body does not come into contact with the other rotating body. 13. The recording apparatus according to claim 12, wherein the rotating body is held at substantially the same height as the projections of the projection group opposed to each other, and at a position inside the another slit. The step between each of the first projections on which the another rotating body is disposed and each of the second projections provided with the slit is at least 0.5 mm or less. 14. The recording device according to claim 13. A roller member having a groove-shaped slit portion facing each of the rotating body and the another rotating body is rotatably supported by the platen, and both side portions of the groove shape of the roller member are The recording apparatus according to any one of claims 8 to 10, and 12 to 14, wherein the recording apparatus is located at substantially the same height as a surface of the platen upstream in the transport direction. 16. The transport unit according to claim 4, wherein the transport unit located downstream of the recording head in the transport direction includes a transport roller pair that sandwiches and transports the recording sheet substantially downstream of the first protrusion in the transport direction. The recording device according to claim 1. The platen has a plurality of concave portions and convex portions extending in the transport direction of the recording sheet, and has a peak at the convex portion with respect to the recording sheet and a valley at the concave portion with respect to the recording sheet upstream of the recording head in the transport direction. The recording apparatus according to claim 1, further comprising a waving shape imparting unit that imparts a waving shape as follows. The waving shape imparting means has a transport roller pair located upstream in the transport direction of the recording head, the convex portion and the concave portion, and a nip position of the transport roller pair is located above the convex portion. In addition, the roller that abuts the non-recording surface of the recording sheet of the transport roller pair and the roller that abuts the other recording surface are offset to the recording head side, so that the recording is performed. The recording apparatus according to claim 17, wherein the recording apparatus is configured to press a sheet against the platen. 18. The recording according to claim 17, wherein the waving shape imparting means is a sheet guide member for guiding a recording sheet to the projections and the depressions, and has a projection for guiding the recording sheet to the depressions. apparatus. 20. The recording apparatus according to claim 19, wherein the projection of the sheet guide member is elastically deformable.

Images